Connector system with thermal management

ABSTRACT

A connector system includes a cage with an intermediate section. The cage support a connector and the resulting connector system includes an upper port and a lower port. A heat sink is provided in the intermediate section that is configured to cool a module inserted into the lower port. Apertures can allow air to flow through the connector system so as to allow for improved cooling by more directly cooling the inserted module. The heat sink can be urged into the lower port by a biasing element.

RELATED APPLICATIONS

This is a continuation application of pending U.S. patent applicationSer. No. 15/237,780, filed Aug. 16, 2016, which claims priority to U.S.Provisional Application No. 62/206,598, filed Aug. 18, 2015, both ofwhich are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

This disclosure relates to field of electrical connectors, morespecifically to the field of input/output (I/O) connectors configured tomanage thermal energy.

DESCRIPTION OF RELATED ART

Input/Output (I/O) connectors are commonly used to provide connectivitybetween boxes or racks of computers, routers and switches. Commonly usedformats of I/O connectors include Small form-factor pluggable (SFP),Quad small form-factor pluggable (QSFP), miniSAS, miniSAS HD and PCIe 8×connectors. These connectors include plugs and receptacles that aredefined by standard bodies and intended to provide reliable performanceregardless of the vendor.

Typical I/O connector systems include a cable assembly and a boardmounted connector. The cable assembly, which commonly includes a pair ofplug connectors on opposite ends of a cable, is configured to transmitsignals over a desired distance. The board mounted connector istypically a receptacle positioned in a panel with the receptacleconfigured to receive and mate with the plug connector.

As data rates have increased, one issue that has been difficult toovercome is the physical limitation of medium that is used to transmitsignals from between the plug connectors. Passive cables, for example,are cost effective for shorter distances but tend to be limited withrespect to distance as signal frequencies increase. Active copper andfiber optic cables are well suited to transmit signals over longerdistances but require power and thus tend to create thermal issues ifthe connector system is not properly designed. One of the major issueswith the increased use of active cables assemblies is the increasedthermal burden the use of such assemblies place on the system.Attempting to cool a module that is placed inside a guide frame or cageis relatively challenging, especially in situations where there are alarge number of ports arranged adjacently (e.g., the front panel densityis high). Thus, certain individuals would appreciate an improvement tothermal management in the receptacle system used in I/O connectors.

BRIEF SUMMARY

A receptacle connector includes cage consisting of an upper port and alower port, each port configured to receive a module. The ports arearranged in a stacked relationship and a board mounted connector ispositioned in the cage and adapted to mate with the modules. Anintermediate space is defined between the ports and includes a heat sinkdisposed in the intermediate space. The heat sink includes a flatportion that extends into the lower port and is configured to slidablyengage, in operation, a module when the module is inserted into theport. A biasing element is used to urge the heat sink to toward themodule so as to maintain continuous pressure between the heat sink andthe module. Fins are formed on the heat sink to increase surface areaexposure. In operation, thermal energy from a module is transferred fromthe module to heat sink and the thermal energy is in turn transferredfrom the heat sink to fins. The cage of connector system is configuredwith apertures so that air flows thorough the cage and across the heatsink fins, thus allowing the removal of thermal energy from theconnector system. Thus the depicted connector system is suitable for usein an architecture such as a rack system that typically directs air fromone side of the rack to the other side of the rack.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limitedin the accompanying figures in which like reference numerals indicatesimilar elements and in which:

FIG. 1 illustrates a perspective view of an embodiment of a connectorsystem.

FIG. 2 illustrates a perspective view of a sectional view taken alongline 1-1 in FIG. 1.

FIG. 3 illustrates a perspective exploded view of the embodimentdepicted in FIG. 1.

FIG. 4 illustrates a perspective partially cut away view of theembodiment depicted in FIG. 1.

FIG. 5 illustrates an elevated plan view of an embodiment of anintermediate section.

FIG. 6 illustrates an elevated side view of the embodiment depicted inFIG. 5.

FIG. 7 illustrates a perspective view of an embodiment of a heat sink incombination with a mounting bracket that supports a biasing element.

FIG. 8 illustrates a perspective view of the embodiment depicted in FIG.7 with the mounting bracket removed.

FIG. 9 illustrates a perspective view of another embodiment of a heatsink in combination with a mounting bracket that supports a biasingelement.

FIG. 10 illustrates a perspective view of the embodiment depicted inFIG. 9 with the mounting bracket removed.

FIG. 11 illustrates a schematic representation of operation of anembodiment such as is depicted in FIG. 1.

DETAILED DESCRIPTION

FIGS. 1-11 illustrate features that can be used to provide a connectorwith desired cooling and it is to be understood that the disclosedembodiments are merely exemplary, and may be embodied in various forms.Specific details disclosed herein are not to be interpreted as limiting,but merely as a basis for the claims and as a representative basis forteaching and enabling one skilled in the art. Therefore, unlessotherwise noted, features disclosed herein may be combined together toform additional combinations that were not otherwise shown for purposesof brevity.

Various configurations have been used to manage thermal energy in I/Oconnectors especially in rack type mounting systems. Typically, the rackincludes a cage configured with an upper port and a lower port. In thesearrangements the upper port is somewhat exposed to the exterior of therack whereas the lower port is positioned with no external visibility.In these arrangements, a heat sink can be readily adapted to engage amodule positioned in the upper port but not to one positioned in thelower port. In these instances, other thermal management structures havebeen employed, such as directed air flow and other thermal transfermethods such as thermally conductive spring fingers adapted to engagethe module and channel the thermal energy to an exterior positioned heatsink. These methods can be costly and use valuable space limitingoptions for adjacently positioned I/O connectors especially in highdensity architecture.

A connector system 1 includes a cage assembly 5 that defines a frontface 6 and a rear face 7 and includes a connector 120 that can bepositioned on a substrate 2 (which may be a standard circuit board orother desirable configuration) and includes an upper port 10 and a lowerport 20 that are each configured to receive mating plug modules. Asillustrated in FIGS. 1 and 2, the connector system 1 includes a stackedconnector 120 having a plurality of laterally spaced wafers that providerows of cantilevered contacts 125 (which are typically positioned in acard slot) and at least one row of cantilevered contacts 125 ispositioned in each port. In a preferred embodiment the connector 120will be adjacent the rear face and spaced apart from the front face suchthat, if the cage assembly was divided into a front half FH (on thefront face side) and a rear half RH then the connector 120 would bepositioned in the rear half RH and would generally not extend into thefront half FH. In typical operation, the connector assembly 1 has thecage assembly 5 disposed around the connector 120 and secured to thecircuit board so as to provide an enclosure that provides desirableproperties. A heat sink 100 is disposed within the cage assembly 5 andis positioned in an intermediate section 70. As depicted, an optionalpair of light pipes 130 can also disposed in the intermediate section 70and, in operation, the light pipes 130 can provide an indication to thestatus of the connection between a module (not shown) and the connector120.

As depicted, the cage assembly 5 includes a body 30, a bottom cover 80and a rear panel 90 that are constructed to form an enclosure. Uponassembly, the cage assembly 5 includes a front opening (associated withthe top port) and a bottom opening. The intermediate section 70 isdisposed within the front opening defining an upper port 10 and a lowerport 20 as best shown in FIG. 1. The stacked connector is positionednext to the rear panel 90 and is spaced apart from the front opening.Gaskets 40, 50 and 60 are secured around the front opening and the frontportion of the intermediate section 70 for providing an electro-magneticinterference (EMI) seal when the connector system 1 is mounted in therack with the gaskets 40, 50 and 60 engaging a bezel (not shown). As isknown, the gaskets 40, 50 and 60 can include resilient spring fingersthat extend into the ports and spring fingers that extend away from theports. As can be appreciated, the spring fingers that extend into theports are configured to engage the body of the module inserted into theports and the outwardly extending spring fingers are configured toengage the bezel.

As illustrated in FIGS. 2-4, the intermediate section 70 is disposed inthe body 30 and helps define the upper port 10 and the lower port 20.The intermediate section 70 is formed including an upper wall 74 and alower wall 73 defining an interior space 79 therebetween. As depicted,the intermediate section 70 includes tabs 77 that protrude into slotsformed in the body 30 and upon secondary forming, secure theintermediate section 70 to the body 30. Naturally, alternative methodsof fastening the intermediate section 70 to the body, such as adhesiveor welding or other know techniques, would also be suitable. Theintermediate section 70 further includes a front portion 71 having aplurality of apertures 71 a formed therein, wherein the apertures can besized to provide appropriate EMI protection.

As illustrated in FIGS. 7-8 a heat sink 100 is formed from a thermallyconductive material and is positioned in the interior space 79 of theintermediate section 70. The heat sink 100 has a body 101 that includesan upper portion 101 a having a plurality of fins 105 formed thereinwith corresponding channels 104 defined between the fins 105 and a lowerportion 101 b. The lower portion 101 b of the heat sink 100 includes aflat surface 102 positioned below the fins 105. The flat surface 102includes a tapered edge 106 at both the front portion adjacent theopening of the connector and the rear end positioned near the connector120. As depicted, a mounting bracket 110 is disposed on the heat sink100 and abuts the fins 105.

In a preferred embodiment a biasing element will urge the heat sink 100into the lower port 20. As depicted, the mounting bracket 110 includesretaining clips 114 that align the mounting bracket 110 to the heat sink100. Biasing elements 112 are formed in the mounting bracket 110 andextend away from the heat sink 100. Both the mounting bracket and theheat sink are inserted into the interior space 79 formed in theintermediate section 70. As illustrated in FIGS. 5-6, the heat sink 100and mounting bracket 110 are disposed between the upper wall 74 and thelower wall 73 with the flat surface 102 of the heat sink 100 extendingthrough a hole 72 formed in the lower wall 73 of the intermediatesection 70. In this configuration, the biasing elements 112 engage theupper wall 74 and force the heat sink 100 against the lower wall 73. Alocating tab 76 is formed in the lower wall 73 of the intermediatesection 70 and is extends into the hole 72. A notch 108 is formed in theheat sink 100 and corresponds to the locating tab 76. As depicted, asecond locating tab 76 is formed on the opposing side of the hole 72 andis matched with a similar recess 108 formed in the heat sink 100. Thetab 76 and recess 108 can be offset across a centerline C of the heatsink 100 so as to help ensure the heat sink 100 is retained in asymmetrical fashion, it being determined that such symmetry can helpallow the heat sink to translate most consistently when, in operation, amodule is inserted into the lower port.

While a biasing element is beneficial as it helps compensate forpositional variance and other tolerances, in an alternative embodimentthe heat sink can be positioned such that it is already correctlyaligned with appropriate tolerance control so that no biasing element isneeded. In another alternative embodiment, a biasing element could beprovided on the floor of the lower port 20. In yet another embodiment,the heat sink could include a thermally conductive and compressiblematerial that is used to take up positional tolerance. Naturally, thesevarious methods of adjusting for tolerance could also be combined (oromitted) as desired. Thus, unless otherwise noted, a particular way ofaddressing tolerances is not required.

As can be appreciated by referring to FIGS. 4 and 5, the cage assemblyis positioned over a connector 120 which is mounted on the correspondingsubstrate (which may be a printed circuit board). The opening formed inthe bottom of the cage 5 allows the connector 120 to be disposed in theinterior of the cage assembly 5 while still mating to a supportingcircuit board. As best illustrated in FIG. 4 the upper port 10 and lowerport 20 are created in the opening defined in part by the intermediatesection 70. As can be appreciated from FIG. 3, the flat surface 102extends through the lower wall 73 and extends into the port 20. Theapertures 32 formed in the side of the cage body 30 allow air AF to flowin and out of the cage assembly 5. Additional apertures 71 a, 62 formedin the front portion of the intermediate section 70 and the intermediategasket 60, respectively, allow air flow AF to pass in and out of thissection of the cage assembly 5. As depicted in FIG. 2, the rear panel 90may include apertures 92 which allows optional air flow AF to enter orleave through the rear panel 90 so as to provide additional paths forthermal energy removal. In embodiments where the connector configurationis ganged and stacked it is expected that air flow AF through the rearpanel 90 will be more important. It should be noted that in anembodiment the arrangement of the apertures in the side and rear of thecage can be positioned so that a majority of the apertures arepositioned in the rear half RH of the cage assembly as this can helpimprove airflow over the heat sink. In a preferred embodiment a majorityof the apertures are positioned rearward of the heat sink, e.g., betweenthe rear face 7 and the heat sink 100.

The depicted heat sink 100 has certain similarities to heat sinks thatare typically known as a riding heat sink. In operation, a module (notshown) is inserted into the lower port 20 and mated with the connector120. In operation, a top surface of the module abuts the tapered edge106 and causes the heat sink 100 to displace/translate upward,deflecting the biasing elements 112 and the biasing elements 112providing a downward reaction force on the heat sink 100 that helpsmaintaining constant contact between the top of the module and the heatsink 100. This allows for improved thermal connection between the heatsink 100 and the inserted module so that thermal energy to be conductedaway from the inserted module into the heat sink and then into the fins.Air flows AF through the cage and through the channels so as to flowpast the fins. This air flow, given the temperature differential, helpsremove thermal energy from the fins and helps allow the heat energygenerated by the module to be dissipated from the connector assembly. Asshown in FIG. 11 a schematic of the thermal flow is depicted. Inoperation, when a module is inserted into a cage, thermal energygenerated by the module is transferred to a heat sink, substantially byconductive heat transfer. This thermal energy is then transferred awayfrom the heat sink primarily by convective heat transfer to a fluid,which typically is air, passing over the heat sink. As can beappreciated, the direction of air flow is not critical to the efficiencyof the system and thus air can flow into or out of the front face of theconnector system. As can be appreciated, however, air flow comes intothe connector system along one face and then exits from a differentface.

It should be noted that while it is preferable to attach the biasingelement 112 directly to the heat sink (as depicted) as it aids inassembly and provides certain manufacturing benefits, such aconstruction is not required. For example, in an alternative embodimentthe biasing element can be mounted directly on the intermediate section70. Thus any desirable biasing element configuration could be used andthe configuration of the biasing element is not intended to be limitingunless otherwise noted.

If not otherwise prevented, upon insertion of a the module into thebottom port the front of the heat sink 100 would be engaged first andthis could cause the front portion of the heat sink 100 to begin to bedisplaced while the rear portion of the heat sink was still in theoriginal position, fully pressed against the lower wall 73. In such anoccurrence the heat sink 100 could become wedged and not move smoothly,potentially causing a significant and undesirable increase in insertionforce. To help ensure insertion forces are properly managed, the tabs 76and recesses 108 previously described provide an aligning feature thatwill keep the heat sink 100 from canting and therefore reduce the chanceof it becoming wedged. Additionally, the tabs 76 and recesses 108 canhelp keep the heat sink in position and can help limit its movementforward or backward within the intermediate section 70 of the cageassembly 5.

In an embodiment the heat sink 100 may include an array of fins 105 withintersecting channels 104 creating a pillar type arrangement, such as isdepicted in FIGS. 9 and 10. In this configuration, air flow AF is notrestricted to a single direction pathway, but can be multi-directionaland flow around the pillars and find the flow path of least resistanceminimizing the possibility of stagnation, as well as increasingturbulence and improving performance. This arrangement also helpsprovide increased surface area of the fins/pillars that can be exposedto the air, which tends to further improve the ability of the system tocool an inserted module.

While various embodiments are contemplated, it should be noted that thedepicted configuration of the thermal pathway between the module and theenvironment is such that the air flow enters and exists the cage throughapertures and flows through channels dissipating the heat energytransferred to the fins of the heat sink. The air flow thorough the cagecan be forced by a fan defining an intake and an exhaust.

The disclosure provided herein describes features in terms of preferredand exemplary embodiments thereof. Numerous other embodiments,modifications and variations within the scope and spirit of the claimsand the disclosure will occur to persons of ordinary skill in the art.

We claim:
 1. A connector system, comprising: a cage with a front face, arear face and two opposing sides that extend between the front and rearface, the cage including an intermediate section that includes an upperwall and a lower wall, the upper and lower walls helping to define anupper port and a lower port in the cage, the lower wall including a holeformed therein so that the intermediate section is in communication withthe lower port; a connector positioned in the cage, the connectorincluding a first row of cantilevered contacts in the upper port and asecond row of cantilevered contacts in the lower port; and a biased heatsink disposed in the intermediate section between the upper and lowerports, the biased heat sink extending through the hole into the lowerport, wherein a mounting bracket is disposed on the heat sink and isconfigured to engage the upper wall in urging the heat sink against thelower wall.
 2. The connector system of claim 1, wherein the mountingbracket is attached to the heat sink.
 3. The connector system of claim2, wherein the mounting bracket includes a biasing element that urgesthe heat sink into the lower port.
 4. The connector system of claim 1,wherein the biased heat sink includes a flat surface that is urged intothe lower port.
 5. The connector system of claim 4, wherein the biasedheat sink includes a plurality of fins, the fins arranged in a pluralityof pillars.
 6. The connector system of claim 1, wherein the intermediatesection includes a front portion with a plurality of apertures providedin the front portion.
 7. The connector system of claim 1, wherein thecage has a front half and a rear half and the connector is positioned inthe rear half and does not extend into the front half.
 8. The connectorsystem of claim 7, wherein a plurality of apertures are provided on atleast one of the sides and rear face of the cage and a majority of theplurality of apertures are positioned in the rear half.
 9. The connectorsystem of claim 8, wherein the majority of the apertures are positionedbetween the heat sink and the rear face.
 10. A connector system,comprising: a cage with a front face, a rear face and two opposing sidesthat extend between the front and rear face, the two opposing sideshelping to define an upper port and a lower port, an intermediatesection positioned in the cage, the intermediate section including anupper wall and a lower wall that help define an interior space, thelower wall defining a top of the lower port, the lower wall including ahole formed therein so that the interior space is in communication withthe lower port; a connector positioned in the cage, the connectorincluding a first row of cantilevered contacts positioned in the upperport and a second row of cantilevered contacts positioned in the lowerport; and a heat sink positioned in the interior space, the heat sinkextending through the hole into the lower port, wherein a biasingelement is disposed on the heat sink and is configured to engage theupper wall in urging the heat sink against the lower wall.
 11. Theconnector system of claim 10, wherein the biasing element urges the heatsink into the lower port.
 12. The connector system of claim 11, whereinthe biasing element is mounted to the heat sink.
 13. The connectorsystem of claim 10, wherein apertures provided on a front portion of theintermediate section are in communication with apertures provided on arear face of the cage.
 14. The connector system of claim 10, wherein theheat sink includes a plurality of fins.
 15. The connector system ofclaim 14, wherein the cage includes apertures on two sides such that, inoperation, air can flow in the apertures on one of the two sides, pastthe fins and out the apertures on the other of the two sides.